Trammel of Archimedes

A trammel of Archimedes is a mechanism that generates the shape of an ellipse. It consists of two shuttles which are confined (trammeled) to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. Use the picture as a guide to put the moving parts in the correct rails during assembly. Don’t tighten the screws too much.